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  • Writer's pictureEinar Páll Svavarsson

How to hike to the volcanic activity in Geldingadalir at Reykjanes Peninsula in Iceland

Updated: Mar 24, 2023


Geldingadalir hike
Geldingadalir hike

On the evening of March 19th, an eruption began on the Reykjanes Peninsula. It was not a surprise as thousands of earthquakes had shaken that region for more than a year. An indication that an eruption could be expected. As is common in Iceland, an eruption begins with a fissure on the surface, and glowing magma begins to float around the region. The fissure can extend for many kilometers, as it extended up to 27 kilometers in Skaftáreldar in 1783. In a matter of days, the magma starts to deliver a constant lava flow through a few craters that form randomly on the fissure. Conveniently, on March 19th, the fissure in Geldingadalir on the Reykjanes Peninsula was only about 500 meters. In a few hours, the immediate delivery of magma concentrated on one crater. At that point, it became clear that this small eruption would most likely turn into a tourist attraction.


Rushing towards the eruption

Your gear for hiking in Iceland
Your gear for hiking in Iceland

Unlike many people who would flee an eruption, Icelanders feel compelled to rush to the site when an eruption begins. Everyone wants to see this spectacular sight. It is not a mystery, as an eruption is one of the most magnificent things one can witness in his lifetime. It is stunning and breathtaking, far beyond the comparison that it is something out of a movie. It is the real deal, and standing so close that you can feel the heat from the magma gushing from the crater and flowing in rivers of fire makes your heart skip a beat. You can almost shake hands with the most powerful natural forces on the planet, and you are just a few kilometers from Reykjavík, the capital of Iceland, and the most populated on our small island.


What kind of eruption – a message from the mantle

Hiking to Geldingadalir volcano
Hiking to Geldingadalir volcano

Most eruptions in Iceland are from the basalt family, and this is also the case at Geldingadalir. The exciting thing about this eruption is that the magma seems to originate deep beneath the crust. The magma from the mantle is at least 20 kilometers beneath the surface. According to geologists, this hasn’t happened in thousands of years, as most Reykjanes eruptions have fed on magma chambers within the crust. It seems that the mantle has found a firetube through the crust straight to the surface. This is what we have learned from the chemical composition of the magma. This defines the eruption as a caldera rather than a crater and could indicate that this small and steady lava flow could last for years, decades, and even centuries. Eventually, the lava would pile up and float towards the ocean on the south shore of the Reykjanes Peninsula.


Before hiking to Geldingadalir valley, there are crucial things to consider



Thousands of Icelanders have hiked to the Geldingadalir valley to see and experience the eruption. It is not a difficult walk, but it requires careful planning and an understanding of the danger. As is customary in Iceland, you begin with the weather. The best weather is a light southerly wind and a clear sky, with a 7 to 34 mph wind speed. The wind will then blow the toxic chemicals north, preferably in your direction.


Understanding and researching the chemicals delivered by magma is crucial and can be found on the Met Official website. It is also important to understand the nature of these toxic chemicals and how and where they settle. The safest place is usually upon the caldera hills, and it is best not to get too close to the valley. Some of the most toxic chemicals are invisible and do not warn that you are about to collapse. So be extremely cautious near the site and never walk into the volcano's smoke.


The regular but important hiking matters you need to prepare for


As shown on the map, the hike starts at road nr. 427 (Suðurstrandarvegur) and is around 2.2 miles to the volcanic activity. The hike back and forth should be a little less than 6.2 miles if you include a stroll on the hills' safe side. Although not a long or difficult hike in any way, it is in an area that is somewhat unpredictable in terms of weather and necessitates the preparation and gear required for any serious hike.


First and foremost, good hiking shoes are required due to the harsh terrain. You also need warm clothing and a rain-resistant jacket and pants as a top layer. It is also good to have a small package of bandaid in your backpack. Water is another significant thing to carry. Remember to start with a full bottle of water. You also need to carry food for the day, like a sandwich, nuts, fruits, chocolate, and vegetables. For all this, you need a good backpack.


For safety, a GPS and a fully charged phone


You do not want to get lost in this area. That is why GPS or a tracking app is essential for this hike. You might find it unnecessary on a good day but remember the weather can change quickly and unexpectedly. It is also good to fully charge the phone before you start and carry it in the inner pocket to preserve the battery from getting drained due to cold. It is also good to carry a power bank if you intend to take many photos with your phone. And last but not least, you should bring a camera.


Photographing the caldera/volcano



I would bring a 14 to 24 mm lens and a 70 to 200 mm lens to take photos. For landscape photography, now is the time to use a telephoto lens. With those two lenses, you can cover all the angles you need at the location, and you can click magnificent photos from the hills around the caldera, even a closeup to the source of the floating lava. There are also out-of-this-world and jaw-dropping stuff to photograph in the lava, such as the river of fire, freshly solidified magma, splashing magma, and the overall formation of the lava with its many red fire lines and fire holes. I could probably go on and on.


A hike that doesn’t come without danger


Finally, I must emphasize that, while this is a once-in-a-lifetime opportunity for most people, it is not without risk. However, with proper planning and caution, you can reduce the risk. On the other hand, it is most likely one of the most incredible sights you will ever lay your eyes on.




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